This invention relates to tree coverings and, more particularly, to an envelope-type covering and method of using the same. While the covering is particularly adapted for use as a frost protector, it may also be used for bird and insect control and, in certain cases, for accelerating fruit maturity.
U.S. Pat. No. 1,820,040, issued Aug. 25, 1931, to Zuckerman, discloses a protective envelope for trees of the general type that is the subject of this invention. This patent illustrates an envelope having an open bottom and closed top with a lifting means affixed to the closed top by which the envelope may be lifted to a position above the tree and thereafter lowered onto it. The bottom or mouth of the envelope is kept open during installation by a circular band of spring steel or the like. Once installation has been completed, the band is removed and a drawstring tightened to close the mouth or bottom of the bag about the trunk of the tree. A small lamp is then placed within the envelope through means of a suitable access opening. The function of the lamp, of course, is to heat the air within the envelope and thus prevent frost damage.
The Zuckerman patent does not address specifically the manner in which the envelope is to be removed from the tree when no longer needed. Removal would be effected, presumably, by loosening the drawstring and thereafter lifting the envelope upwardly in much the same manner as it had initially been placed over the tree. This method of removal would not necessitate reattachment of the spring steel member which had held the mouth or bottom of the envelope open during installation. It could, however, cause serious damage to the tree, particularly delicate blossoms and fruit, due to the frictional contact of the interior of the envelope therewith during the removal process. It would also necessitate fabrication of the envelope from fairly heavy material to minimize tearing of the envelope during the removal process. And, of course, the heavier the envelope material, the more likely damage to the tree during removal of the envelope.